In order to retrieve an object placed in one of a plurality of placement destinations, the placement destination in which the object is placed needs to be specified. A placement destination in which an object is placed includes, for example, a storage device, a storage medium, a place, and a physical location. For example, by storing an object and a relation (relevance) with a placement destination in which the object is placed, the placement destination in which the object is placed can be specified. When a placement destination in which an object is placed cannot be specified quickly, it is difficult to access the object quickly. When storing all relations between objects and placement destinations in which the objects are placed, increase in the number of objects entails increase in storage capacity required for storing the relations between the objects and the placement destinations. When a vast number of objects are placed, a vast number of relations need to be stored. Additionally, the stored vast number of relations need to be maintained not to be lost. In order to store the vast number of relations, a cost of a storage device storing the vast number of relations is required. Maintaining the stored vast number of relations without losing the relations requires a yet higher cost.
A method of specifying a placement destination in which an object is placed without storing a relation between the object and the placement destination of the object includes, for example, a method of uniquely determining the placement destination of the object on the basis of an identifier of the object and the like.
An example of a device using such a technology is disclosed, for example, in PTL 1. The device according to PTL 1 generates a pseudorandom number by using an identifier of an object as a seed. The pseudorandom number is determined uniquely to the seed. Further, a generation probability of the pseudorandom number is uniform throughout a value range of the pseudorandom number. The device according to PTL 1 determines a placement destination related to a range of values including the generated pseudorandom number, as a placement destination of the object, on the basis of a table storing a relation between a range of values and a placement destination. The device according to PTL 1 repeats generation of a pseudorandom number until a pseudorandom number included in a range of values related to a placement destination is generated.